Induction burner

ABSTRACT

An induction burner for effectively and efficiently burning fuel to supply heat; or alternatively to efficiently consume contaminants in an air stream prior to discharging the air stream to the atmosphere; wherein the burner is a refractory body having an axial passage for a flame, a plurality of passages conducting air from a combustion chamber to an induction port header, which in turn communicates with the axial passage, a generally radial enlargement in the axial passage, a flame tunnel at one end of the axial passage, the flame tunnel having a diameter less than the radial enlargement.

Oct. 7, 1975 United States Patent [191 Voorheis INDUCTION BURNER Primary ExaminerCarroll B, Dority, Jr,

Attorney, Agent, or FirmPopper & Bobis [57] ABSTRACT An induction burner for effectively and efficiently burning fuel to supply heat; or alternatively to effi- [22] Filed:

[52] US. Cl. 431/116; 431/285; 431/353 ciently consume contaminants in an air stream prior to F23L 17/00 discharging the air stream to the atmosphere; wherein 431/115, 1 16, 285, 353; the burner is a refractory body having an axial passage for a flame, a plurality of passages conducting air from a combustion chamber to an induction port header,

which in turn communicates with the axial passage, a

generally radial enlargement in the axial passage, a

.I F ll 8 55 ll [56] References Cited UNITED STATES PATENTS flame tunnel at one end of the axial passage, the flame tunnel having a diameter less than the radial enlarge- 431/116 mem 431/1 15 La Haye et a1. 431/115 10 Claims, 2 Drawing Figures 3,174,526 3/1965 Von 3,516,807 6/1970 West et al,........ 3,868,211 2/1975 US. Patent 0a. 7,1975

FIG 1 I I I x 1/ FIG. 2

o X 8 I INDUCTION BURNER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to duct fired induction burners generally. and specifically to duct fired induction burners having therein passages to supply air to support combustion drawing from a combustion chamber to the point of flame propagation in the burner, and further to such a burner having a flame eddy cavity adjacent to a flame tunnel which cavity is higher than the flame tunnel.

2. Prior Art There are numerous induction burners which have been in use for many years. Problems arise from time to time with their use, in that flame-outs are frequent. Their design is such that they support combustion in part with clean primary air, which is not necessary to support combustion when the burner is being used to consume contaminants in secondary contaminated air introduced into a combustion chamber.

SUMMARY OF THE INVENTION It has been found that an induction burner can be devised which utilizes solely to support combustion, the atmosphere of the combustion chamber, and predominantly that portion of the atmosphere of the combustion chamber which has not been subjected to combustion. This burner efficiently consumes the undesirable contaminants in the air or gases introduced into the combustion chamber by utilizing such gases to support combustion. In addition, this burner is provided with an anti-flame-out construction in the form of a flame eddy cavity. whereby the failure of the burner to adequately and properly support combustion due to high velocity gas introduction is substantially and effectively avoided.

DESCRIPTION OF THE DRAWINGS The objects and advantages as well as other objects and advantages may be attained by the device shown by way of illustration in the drawings in which:

FIG. 1 is a vertical section view of my induction burner; and

FIG. 2 is a backend view thereof.

PREFERRED EMBODIMENT Referring now to the drawings in detail, the induction burner 11 is provided with a tubular cylindrical shell 12, preferably made of steel although other materials may be used. The shell is provided with a closure plate 13 at one end, also preferably steel.

The closure plate 13 has a central circular, axial orifice l4 defining a fuel gun port, whereby liquid or gaseous fuel is introduced into the burner 11. The shell 12 surrounds a unitary elongated refractory, body or lining 10. The body fills the space defined by the shell 12 and the closure plate 13. The refractory body 10 has a first passage which is a generally radial, small, axial bore in registration with the fuel supply port 14 in the plate 13.

The first passage 15 communicates with a first cham ber 16 in the refractory body 10. This first chamber 16 defines a header for induction ports which hereafter will be referred to. The header 16 is radially high and extends nearly to the shell 12. From the first chamber 16, there is a second passage 17, defining a conduit whereby fuel from the fuel supply orifice l4 and air to support combustion from the first chamber or induction port header 16 are conducted into a second chamber 18 which is a radial annular cavity 18, which functions as a flame retention chamber.

The second chamber 18 is a flame eddy-cavity. It is larger than the second passage 17, and defines an area to capture the flames of combustion in order to prevent a flame-out. Beyond the second chamber 18 is a gener ally elongated open chamber 19 which defines a flame tunnel wherein combustion occurs and from which issues the flame plume 20.

Surrounding the flame tunnel 19 in the refractory fire-brick lining 10, there are a plurality of tubular bores 21, whereby air to support combustion is conducted from the furnace wall area via induction ports into the bores 21 to the induction port header 16. It will be seen that the bores 21 are spaced away from the plume 20, whereby the products of combustion are not necessarily returned through the bores 21 to the point of the flame propagation. The bores 21 primarily will conduct the air embodying the waste process products from along the walls of a combustion chamber back to the point of propagation of the flame. It will be seen that there is no passage communicating between the flame tunnel l9 and the bores 21 in the refractory body, through which air to support combustion is supplied to the first chamber 16; it is only incidental to the combustion that takes place in the combustion chamber that products of combustion may in part be returned through the bores 21 to the induction port header or first chamber 16. This burner 11 is primarily designed for waste gas-streams, wherein the gas stream has undesirable impurities which must be removed or converted to less undesirable products of combustion before being discharged to the atmosphere. It is however to be understood that this burner may have, in addition other uses.

Waste gas-streams carrying undesirable products which are to be eliminated from such streams are usually rich in oxygen to support combustion so that when such waste gas-streams are supplied to a combustion chamber to which the present burner is attached, there will be ample oxygen in the combustion chamber to support combustion and, indeed, to enter the bores 21 and the induction port header 16 to support combustion.

It will be further noted that this burner utilizes as a primary source of oxygen: the waste gas-stream, in order to support combustion, and no provision is made for the utilization of a secondary source of oxygen at the site of the combustion. In this manner, large economies are effected in the disposition of the impurities.

.The burner is provided with a pilot 22 which extends through the portion of the refractory brick 10 lying over the closure plate 13, whereby a flame for ignition of gas or oil fuel may be provided in the induction port header. In order to insure that fuel will not be introduced continually into the burner 11 if there should be a failure of ignition, a scanner connection 23 is provided for the flame eddy cavity 18. A scanner applied to this connection would continuously monitor the existence of combustion. There is a further scanner connection 24 which monitors the existence of the pilot flame. Flame Scanners are well known to the industry. In the event ofa failure of the pilot flame, the combustion in the eddy cavity 18, the scanner will send a signal to the fuel supply source which will immediately cut off fuel. A burner gun is not shown in the burner 11. It is attached at the fuel supply port 14. Such burner flame guns may be in accordance with the many guns now well known, or may be particularly in accordance with disclosures in my US. Pat. No. 3,758,259 issued Sept. 11, 1973, wherein details of the construction of the suitable burner gun are set forth in detail.

The refractory lining of the induction burner may be made of any suitable refractory material and which is castable and composed of 47 to 96 per cent alumina.

Typical induction burner dimensions suitable to accomplish the purposes of the present invention are as follows:

The first and second chambers l6, 18 may be 3 inches wide. 7

The first chamber 16 should be higher than the second chamber 18; a typical dimension for the height of the first chamber 16 is 26 inches and the second chamber 18: 14 inches.

The elongated open chamber 19 should be less in height than the second chamber 18 and may be approximately 8 inches high.

The second passage 17 communicating between the first chamber 16 and the second chamber 18 should be generally of the same height as the elongated open chamber 19: 8 inches.

The length of the elongated open chamber 19 should be approximately one and one-half to twice its diameter.

The first passage should be approximately 3 inches high.

The first chamber 16 may be typically 26 inches high and 3 inches wide. Tubular bores 21 communicating between the induction port and the first chamber 16 should be approximately 18 inches long.

What is claimed is:

1. An induction burner comprising:

a. an elongated refractory body,

b. a first passage at the front of the body for the introduction of fuel,

c. a first chamber in the body connected with the first passage, and defining a header for induction ports,

d. a second passage in the body communicating with the first chamber,

e. a second chamber in the body communicating with the second passage, and defining a radially dead end flame eddy cavity,

f. an elongated chamber having an opening to the ambient in a back face of the body, connected to the second chamber, and defining a flame tunnel, said second chamber being substantially larger in a radial direction than said second passage and said elongated chamber,

g. an induction port open to the ambient and located in the back face of the body adjacent the opening in the elongated chamber, connected with the header.

2. An induction burner according to claim 1 and a. a metal shell surrounding the body,

b. a front plate on the front of the body.

3. An induction burner according to claim 1 and a. the body having a generally circular cross-sectional configuration,

b. the first passage, first chamber, second passage, second chamber, and open chamber being all of a generally circular, cross-sectional configuration.

4. An induction burner according to claim 3 and a. the first passage, first chamber, second passage,

second chamber, and open chamber being disposed co-axially.

5. An induction burner according to claim 1 and a. the first chamber and the second chamber having generally the same width.

6. An induction burner according to claim 1 and a. the first chamber being radially generally greater than the second chamber.

7. An induction burner according to claim 1 and a. the second chamber being radially generally greater than the open chamber.

8. An induction burner according to claim 4 and a. the elongated open chamber being axially longer than the second chamber.

9. an induction burner according to claim 1 and a. a plurality of additional induction ports at the back face of the body, connected with the header.

10. An induction burner comprising:

a. an elongated refractory body,

b. a first passage at the front of the body for the introduction of fuel,

c. a first chamber in the body connected with the first passage, and defining a header for induction ports,

d. a second passage in the body communicating with the first chamber,

e. a second chamber in the body communicating with the second passage, and defining a radially dead end flame eddy cavity,

f. an elongated chamber having an opening to the ambient in a back face of the body, connected to the second chamber, and defining a flame tunnel, said second chamber being substantially larger in a radial direction than said second passage and said elongated chamber,

g. an induction port open to the ambient and located in the back face of the body adjacent the opening in the elongated chamber, connected with the header,

h. a metal shell surrounding the body,

i. a front plate on the front of the body,

j. the body having a generally circular cross-sectional configuration,

k. the first passage, first chamber, second passage, second chamber, and open chamber being all of a generally circular, cross-sectional configuration,

l. the first passage, first chamber, second passage,

second chamber, and open chamber being disposed co-axially,

m. the first chamber and the second chamber having generally the same width,

11. the first chamber being radially generally greater than the second chamber,

0. the second chamber being radially generally greater than the open chamber,

p. the elongated open chamber being axially longer than the second chamber,

q. a plurality or additional induction ports at the back of the body, connected with the header. 

1. An induction burner comprising: a. an elongated refractory body, b. a first passage at the front of the body for the introduction of fuel, c. a first chamber in the body connected with the first passage, and defining a header for induction ports, d. a second passage in the body communicating with the first chamber, e. a second chamber in the body communicating with the second passage, and defining a radially dead end flame eddy cavity, f. an elongated chamber having an opening to the ambient in a back face of the body, connected to the second chamber, and defining a flame tunnel, said second chamber being substantially larger in a radial direction than said second passage and said elongated chamber, g. an induction port open to the ambient and located in the back face of the body adjacent the opening in the elongated chamber, connected with the header.
 2. An induction burner according to claim 1 and a. a metal shell surrounding the body, b. a front plate on the front of the body.
 3. An induction burner according to claim 1 and a. the body having a generally circular cross-sectional configuration, b. the first passage, first chamber, second passage, second chamber, and open chamber being all of a generally circular, cross-sectional configuration.
 4. An induction burner according to claim 3 and a. the first passage, first chamber, second passage, second chamber, and open chamber being disposed co-axially.
 5. An induction burner according to claim 1 and a. the first chamber and the second chamber having generally the same width.
 6. An induction burner according to claim 1 and a. the first chamber being radially generally greater than the second chamber.
 7. An induction burner according to claim 1 and a. the second chamber being radially generally greater than the open chamber.
 8. An induction burner according to claim 4 and a. the elongated open chamber being axially longer than the second chamber.
 9. an induction burner according to claim 1 and a. a plurality of additional induction ports at the back face of the body, connected with the header.
 10. An induction burner comprising: a. an elongated refractory body, b. a first passage at the front of the body for the introduction of fuel, c. a first chamber in the body connected with the first passage, and defining a header for induction ports, d. a second passage in the body communicating with the first chamber, e. a second chamber in the body communicating with the second passage, and defining a radially dead end flame eddy cavity, f. an elongated chamber having an opening to the ambient in a back face of the body, connected to the second chamber, and defining a flame tunnel, said second chamber being substantially larger in a radial direction than said second passage and said elongated chamber, g. an induction port open to the ambient and located in the back face of the body adjacent the opening in the elongated chamber, connected with the header, h. a metal shell surrounding the body, i. a front plate on the front of the body, j. the body having a generally circular cross-sectional configuration, k. the first passage, first chamber, second passage, second chamber, and open chamber being all of a generally circular, cross-sectional configuration, l. the first passage, first chamber, second passage, second chamber, and open chamber being disposed co-axially, m. the first chamber and the second chamber having generally the same width, n. the first chamber being radially generally greater than the second chamber, o. the second chamber being radially generally greater than the open chamber, p. the elongated open chamber being axially longer than the second chamber, q. a plurality or additional induction ports at the back of the body, connected with the header. 